Gen Xers, the generation that followed baby boomers, used to be known as the skeptical slackers.

Now a new study finds that young Millennials may be just as gloomy — or even more so.

When boomers were coming of age in the mid-1970s, about a third of high school seniors agreed that "most people can be trusted."

That dropped to 18 percent in the early 1990s for Gen Xers. Then, in 2012, just 16 percent of Millennials said they trusted most people, according to the study, to be published early this month in the online edition of the journal Psychological Science.

Researchers also found that Millennials' confidence in institutions, from Congress to Wall Street and beyond, dropped sharply in the decade following the terror attacks of September 2001.